In the interior of a warehouse (an automatic warehouse) of, for example, a distribution center or the like, a seismically isolated floor is sometimes adopted in order to prevent collapse of cargo due to swaying of a rack accommodating cargo at the time of an earthquake. On the other hand, outside (in a cargo handling building or the like) of the warehouse, a normal floor rather than a seismically isolated floor is provided in order to reduce construction costs. A transport dolly is used for the transport of a cargo between a seismically isolated floor area and a normal floor area, and a first rail on which the transport dolly travels is laid on the seismically isolated floor, and a second rail is laid on the normal floor to be connected to the first rail.
In such a transport system, in a case where when the seismically isolated floor and the normal floor move relative to each other at the time of earthquake, a connection portion between the first rail and the second rail is damaged and each rail is bent and deformed, it takes a long time to repair this after the earthquake. Therefore, a transport system made such that a connection rail is interposed between a first rail and a second rail, and the connection rail is actively disconnected when the first rail on a seismically isolated floor and the second rail on a normal floor move relative to each other at the time of an earthquake, is proposed (refer to, for example, Patent Document 1).